Venerable Euphrosyne of Polotsk, princess and abbess.
Euphrosyne was a princess of Polotsk who refused marriage and became a nun in her youth. She founded a convent and a monastery in Polotsk, copied books, and encouraged learning among her people.
Toward the end of her life she went on pilgrimage to Jerusalem, where she reposed in 1173.
Feast day
On the New Calendar, Euphrosyne of Polotsk is commemorated on May 23. Churches on the Old (Julian) Calendar keep the feast on June 5 of the civil calendar.
Also commemorated on May 23

Mary of Clopas
Holy Woman, Μαρία του Κλωπά
Saint Mary the wife of Clopas, one of the Myrrhbearing Women.
Eumenios of Crete
Venerable, Ευμένιος ο Νέος (Σαριδάκης)
Venerable Eumenios the New (Saridakis), the God-bearing elder of the leper colony of Athens.
Joachim of Ithaca
Venerable, Ιωακείμ ο Ιθακήσιος
Venerable Joachim of Ithaca, called Papoulakis, ascetic and wonderworker of the Ionian Islands.
Manaen the Prophet
Apostle, Μαναήν ο Προφήτης
Saint Manaen, prophet and teacher of the Church of Antioch, named in the Acts of the Apostles.